This project will provide a test of four antigens on adult and juvenile Macacas on Cayo Santiago, Puerto Rico. One problem is to determine the percent of positive antibody titers that can be determined from the adult sample for whom blood sera are presently available, and the number of juveniles that should be sampled. The monkey colony on Cayo Santiago will be trapped in January of 1984, at which time the remaining monkeys will be bled and the antibody titers analyzed.